【发布时间】:2014-01-22 03:46:05
【问题描述】:
我正在努力将二维点数组转换为一维整数数组。我写了一个包装类来为我做这件事(Array3D),它为我做映射填充底层缓冲区,但看起来索引完全错误,因为当我打印我的二维数组并比较缓冲区时,它给我不同的输出。
二维点数组的维度为 steps × number_of_robots。因此,一维缓冲区有 步长 × number_of_robots × 2。
想法是这样的
buffer[index(x,y,0)] corresponds to points[index(x,y)].x
buffer[index(x,y,1)] corresponds to points[index(x,y)].y
输出错误,因为当我打印出 2D 点数组和 1D 缓冲区时,它应该是相同的。我从文件中读取了这一行点,因此它们应该完全一样。
这些点来自文件读取的输入。如何做到这一点似乎并不重要。事实上,main.cpp 的输出是:
(0, 4) (0, 5) (1, 5) (2, 5) (2, 4) (3, 4) (2, 4) (2, 3) (2, 2)
(4, 0) (4, -1) (4, 0) (4, 1) (3, 1) (4, 1) (4, 2) (3, 2) (2, 2)
(0, 2) (0, 3) (1, 2) (2, 2) (2, 2) (3, 3) (2, 2) (2, 2) (2, 2)
(1, 2) (2, 2) (2, 2) (3, 3) (2, 2) (2, 2) (2, 2) (3, 3) (2, 2)
point.cpp
Point::Point(int a, int b) {
x = a;
y = b;
}
Array3D.cpp
template<class T>
int Array3D<T>::index(int x,int y, int z) {
return (x * ydim + y) * zdim + z;
}
template<class T>
T Array3D<T>::get( int x, int y, int z) {
return buffer[index(x,y,z)];
}
template<class T>
void Array3D<T>::set( int x, int y, int z ,T n) {
buffer[index(x,y,z)] = n;
}
Harvester.cpp
int Harvester::index(int t, int n) {
return t*number_of_robots + n;
}
void Harvester::extract(Array3D<int> *array) {
Point p;
for(int t = 0; t < steps; t++ ) {
for(int n = 0; n < number_of_robots; n++) {
p = data[index(t,n)];
array->set(t,n,0,p.x);
array->set(t,n,1,p.x);
}
}
}
void Harvester::read_points(string filename) {
string line;
ifstream input;
input.open(filename.c_str());
input >> number_of_robots;
int x, y;
for(int n = 0; n < number_of_robots; n++) {
if(input >> x >> y) {
data[index(0,n)].x = x;
data[index(0,n)].y = y;
//cout << x << " " << y << endl;
} else {
cout << "Your file is bad, and you should feel bad!";
return;
}
}
}
void Harvester::print_harvest() {
for (int n = 0; n < number_of_robots; n++) {
for (int t = 0; t < steps; t++) {
data[index(t,n)].dump();
}
cout << endl;
}
cout << endl;
}
robots_002.txt
2
0 4
4 0
main.cpp
int main() {
int mission_time;
int number_of_robots;
Point goal;
string path;
bool print = true;
int choice = 2;
mission_time = 8;
number_of_robots = 2;
goal.x = 2;
goal.y = 2;
path = "robots_002.txt";
int steps = mission_time + 1;
Harvester h(mission_time, number_of_robots, goal);
h.read_points("fixtures/" + path);
h.run();
int *buffer = new int[steps * number_of_robots * 2];
Array3D<int> arr(steps, number_of_robots, 2, buffer);
h.extract(&arr);
h.print_harvest();
for (int n = 0; n < number_of_robots; n++) {
for (int t = 0; t < steps; t++) {
printf("(%d, %d)\t", arr.get(t, n, 0), arr.get(t, n, 1));
}
cout << endl;
}
return 0;
}
【问题讨论】:
-
所以输出是错误的,但是你没有显示输入,甚至没有解释输出是怎么错的。祝你好运......
-
我认为很明显,当我想映射某些东西时,两者的输出应该是相同的。我对此添加了更多解释。
标签: c++ arrays multidimensional-array mapping